JP2001175072A - Image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To solve instability in an image due to the amount of recycled toner since the ratio of existence of recycled toner and unused toner inside a developing container can only be detected vaguely. SOLUTION: In the device, a recovery container 68 where the recycled toner recovered by a cleaning device 6 is accumulated is provided, the quantity of the recovered toner inside the recovery container 68 is detected and the ratio of mixture is controlled according to the detected result. The ratio of existence of recycled toner and unused toner inside the developing container 41 is calculated from the ratio of mixture of the replenished toner. Furthermore, the toner concentration control is switched over according to the ratio of mixture.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a copier, a laser printer, a facsimile, and the like, and more particularly to an image forming apparatus for performing recycle development using electrophotographic technology.

[0002]

2. Description of the Related Art A conventional image forming apparatus for performing recycle development will be described with reference to FIG. This has a generally used electrophotographic process, in which a charge is applied to the surface of the photosensitive drum 1 by a main charging unit 2,
The image is exposed by the laser light of the laser optical system unit 3, and the formed electrostatic latent image is visualized by toner charged to the same polarity as the potential of the photoconductor surface in the developing device 4. The developed image is transferred to the conveyed sheet by the transfer unit 51. Untransferred toner is partially present on the surface of the photosensitive drum 1 on which the developed image has been transferred to paper,
This is scraped off by the blade 62 of the cleaning device 6, and the surface of the surface is returned to near 0 V by irradiating light with the neutralization lamp 7 to prepare for the next cycle again. On the other hand, the recycled toner collected by the cleaning device 6 passes through the recycled toner conveying path 67 and is returned to the developing device 4.
The toner is fed into a toner hopper at the upper part of the printer, mixed with unused toner, and then fed again into the developing container in response to a toner supply signal.

[0003]

However, according to such a conventional method, the image deteriorates when the amount of the recycled toner is large, and the same T / D (toner weight / toner weight) depends on the mixing ratio of the unused toner and the recycled toner. In spite of the problem that the output value of the toner is different (percentage of the developer weight), all of the collected toner is re-introduced into the developing container. This is because the recycled toner is a toner that has been used once, so its charging performance is worse than that of the unused toner, the repulsion between the developer particles is reduced, the density of the developer is increased, and the output of the toner sensor is unused. This is because the value is higher than that of the developer having the same T / D containing only the toner. For this reason, when the ratio of the recycled toner increases in the T / D detection by the normal magnetic permeability sensor, it is determined that the T / D is lower than that of the same T / D of the normal developer, and the defect such as the over toner is determined. Had occurred. Therefore, as disclosed in Japanese Patent Application Laid-Open No. Hei 8-286513 (the amount of unused toner is controlled in accordance with the amount of transported recycled toner and the mixing ratio is suppressed to a predetermined value or less), the amount of recycled toner and unused toner is reduced. There is a description of controlling the mixing ratio. However, even when this technique is used, the amount of recycled toner due to repetition of image formation is not stable, so the mixing ratio of the mixed toner generated is less than a predetermined value, but is not stable, and the amount of recycled toner is large. In this case, there is a concern that a mixed toner is generated more than necessary. For this reason, there is a demand for a technique that detects the ratio of the unused toner and the recycled toner in the developing container and controls the T / D and other conditions accordingly. Also, if the ratio of unused toner and recycled toner in the developing container becomes unknown for some reason, the above control may become meaningless, so change the unknown ratio to the desired ratio. Some technologies are also desired.

[0004]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention provides, as a first invention, an image forming apparatus for performing recycle development in which toner collected by a cleaning device is resupplied to a developing container. Unused toner replenishing means for replenishing unused toner to the developing container, a collecting container for storing the toner collected by the cleaning device, recycled toner detecting means for detecting the amount of recycled toner in the collecting container, and recycling of the collecting container. Recycled toner replenishing means for replenishing toner to the developing container, toner concentration detecting means for detecting a ratio of carrier to toner in the developing container, and toner concentration controlling means for controlling toner concentration based on an output value of the toner concentration detecting means And temporarily calculate the ratio of recycled toner to unused toner in the developer container. Holding means for holding, a calculation result of the ratio of the recycled toner and the unused toner of the developer in the previous developer container held in the holding means, ON control of the unused toner replenishing means, and the recycling A real-time presence ratio calculating unit that calculates and outputs the presence ratio of the recycled toner and the unused toner in the developing container in real time based on the mixing ratio, the amount of the supplied toner, and the supply time obtained from the ON control of the toner supply unit An image forming apparatus is provided.

According to a second aspect of the present invention, there is provided an image forming apparatus for performing recycle development in which toner collected by a cleaning device is resupplied to a developing container. A collection container for storing the collected toner in the collection container, a recycled toner detection unit for detecting the amount of recycled toner in the collection container, a recycled toner supply unit for supplying the recycled toner in the collection container to the development container, and a carrier in the development container. A toner concentration detecting means for detecting a toner ratio,
A toner density control means for controlling a toner density based on an output value of the toner density detection means, a calculation result of an existing ratio of a recycled toner and an unused toner of a developer in a developing container, and an ON time of the unused toner replenishment means Means for storing the history of the recycle toner supply means and the history of the ON time of the recycle toner replenishing means, and the calculation result of the ratio of the recycled toner and the unused toner of the developer in the previous developer container stored in the storage means And an abundance ratio calculating means for calculating the abundance ratio of the unused toner and the recycled toner in the current developing container from the history of each replenishment time.

According to a third aspect of the present invention, there is provided an image forming apparatus for performing recycle development in which toner collected by a cleaning device is re-supplied to a developing container. A collecting container for storing the collected toner in the collecting container, a recycled toner detecting means for detecting an amount of recycled toner in the collecting container, a recycled toner supplying means for supplying the developing container with the recycled toner in the collecting container, and a toner for supplying the developing container. Mixing ratio control means for controlling the mixing ratio between the recycled toner and the unused toner, and the mixing ratio when the existence ratio of the unused toner and the recycled toner in the developing container is unknown or when it is determined that there is a large error. The control means keeps the mixing ratio of the recycled toner and the unused toner for a predetermined time constant. More, to provide an image forming apparatus characterized by having an existence ratio of the fresh toner and the recycled toner in the developing container and a presence ratio resetting means for performing a control to substantially the same as the mixing ratio.

According to a fourth aspect of the present invention, the control content of the toner density control means is switched in accordance with the ratio of unused toner and recycled toner in the developing container.
An image forming apparatus according to a first aspect or a second aspect is provided.

[0008]

According to the first aspect of the present invention, the amount of the recycled toner in the collection container is detected, and the means for supplying the recycled toner and the means for supplying the unused toner can be individually moved. Since the mixing ratio of the unused toner can be controlled, and the amount of the toner consumed from the developing container and the amount of the supplied toner are almost equal,
Further, the present ratio of the recycled toner and the unused toner in the developing container is calculated in real time from the ratio of the recycled toner and the unused toner in the developing container before a predetermined time.

According to the second aspect of the present invention, the amount of recycled toner in the collection container is detected, and the means for supplying recycled toner and the means for supplying unused toner can be moved individually. The mixing ratio of unused toner can be controlled. The existence ratio of the unused toner and the recycled toner in the developing container is calculated from the mixing ratio of the supplied toner and the history data of each supply time.

According to a third aspect of the present invention, the ratio of the unused toner and the recycled toner in the developing container is substantially equal to the ratio after a predetermined time if the mixing ratio of the supplied unused toner and the recycled toner is constant. Using the convergence to the mixture ratio, the error of the existence ratio is reset.

According to a fourth aspect, according to the first or second aspect, it is possible to know the existence ratio of the unused toner and the recycled toner in the developing container, and to control the optimum toner concentration in advance according to the existence ratio. Since the control contents of the means are prepared and switched, an appropriate T / D is maintained.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An image forming section of an image forming apparatus employing an embodiment of the present invention will be described with reference to FIG. First, an electric charge is applied to the surface of the photosensitive drum 1 by the main charging unit 2, an image is exposed by a laser beam of the laser optical system unit 3, and the formed electrostatic latent image is a potential of the photosensitive member surface in the developing device 4. The developed image is formed by the toner charged to the same polarity as the toner image, and the developed image by the charged toner is transferred to the conveyed sheet by the transfer unit 51. The untransferred toner is partially present on the surface of the photosensitive drum 1 on which the developed image has been transferred onto the paper. Is returned to near 0 V, and is ready for the next cycle again. Unused toner is replenished when unused toner is sufficiently stored in the toner hopper 49.
When the unused toner supply motor 47 rotates in response to the toner supply signal, the sponge roller 48 rotates to supply toner to the developing container 41. On the other hand, the recycled toner collected by the cleaning device 6 is temporarily stored in a collection container 68, and then conveyed by the rotation of the recycle toner supply motor 65 and the rotation of the spiral 66 in the recycle toner conveyance path 67. It is thrown into.

The method of collecting and supplying recycled toner will be described in more detail. The collection container 68 is provided with a toner amount detection sensor 69, and may be a photo sensor, a level sensor, or the like, as long as it can detect the amount of recycled toner in the collection container 68 with a certain degree of accuracy. In the present embodiment, a photo sensor 69 is mounted at a predetermined height position on the wall surface of the collection container, and when the photo sensor 69 does not detect toner, it is determined that the amount of recycled toner in the collection container 68 is small, When the sensor 69 detects toner, the collection container 68
It is determined that the amount of recycled toner inside is large. By increasing the number of photo sensors, the amount of recycled toner in the collection container 68 can be detected more finely, and instead of a photo sensor, a level sensor (vibrating the sensor surface to determine how far the object is in contact with the surface) It is also conceivable to use a sensor that outputs a signal. The amount of the recycled toner in the collection container 68 is detected by the above-described method, and the ON / OFF control of the recycled toner supply motor 65 is performed in accordance with the result, so that the unused toner and the recycled toner supplied to the developing container 41 are controlled. Is changing the ratio. In this embodiment, the replenishment amount of the recycle toner is determined by the recycle toner replenishment motor 65O.
At the time of N, the supply amount of the unused toner is 0.05 g / sec, and the supply amount of the unused toner is 0.1 g / sec.
%. Table 1 below shows the correspondence with the detection result of the toner amount detection sensor 69.

[0014]

[Table 1]

It goes without saying that the control unit is informed of the ratio of the unused toner and the recycled toner of the replenishment toner. Here, the mixing ratio of the replenishment toner and the existence ratio of the unused toner and the recycled toner in the developing container 41 are not the same. Therefore, in the first embodiment employing the first invention, the calculation is performed by the following formula.

Carrier: C (g) Toner: T (g) (recycle R, unused M) T / D = T / (C + T) (%) Consumed toner amount = S (g) Recycled toner supply amount = r (g / sec); a predetermined amount is set. Unused toner supply amount = m (g / sec): A predetermined amount is set. Recycling toner amount = chi (g) - as unused toner amount = [psi (g) - original recycled toner amount chi _0-original unused toner amount [psi _0, control further the toner density is maintained at a constant value Is performed, T / D = T / (C + T) = C
From onst, S ≒ (r + m) × △ t. ◎ When recycle toner + unused toner is supplied ・ χ ₀ + △ χ = χ _0- ｛χ / (χ + ψ) × S｝ + r × △ t ・ ψ ₀ + △ ψ = ψ _0- ｛ψ / (χ + ψ ) × S｝ + m × △ t (where, when only recycled toner is supplied, r
= 0 and m = 0 when only unused toner is supplied.
Becomes From the above, ・ △ χ / △ t =-｛χ / (χ + ψ)｝ × (r + m) + r ・ △ ψ / △ t =-｛ψ / (χ + ψ)｝ × (r + m) + m
(R, m are constants) χ + ψ = χ ₀ + ψ ₀ (χ ₀ , ψ ₀ is an initial value) From this, as a = − (r + m) / (χ ₀ + ψ ₀ ), χ = ｛(aχ ₀ + r) e ^{at -r} / a · ψ =} { a ^{_{(aψ 0 + m) e at}} -m} / a.

Here, for example, χ ₀ = 0 g, ψ ₀ = 50 g, r
= 0.05 g, m = 0.1 g, that is, calculation results after 0 to 1,200 seconds when toner containing about 33% recycled toner is injected into the developer containing only unused toner Are shown in Table 2.

[0018]

[Table 2]

Next, for example, χ ₀ = 10 g, ψ ₀ = 40 g,
The condition of r = 0.05 g and m = 0.1 g, that is, about 3%
Table 3 shows the calculation results after 0 to 1,200 seconds when toner containing 3% recycled toner is supplied.

[0020]

[Table 3]

Next, for example, χ ₀ = 10 g, ψ ₀ = 40 g,
The calculation results after 0 to 1,200 seconds under the condition of r = 0 g and m = 0.1 g, that is, when only unused toner is added to the developer using toner already containing 20% of recycled toner. It is shown in FIG.

[0022]

[Table 4]

As can be seen from Tables 2, 3 and 4, the calculated results show that the percentage of recycled toner in the developing unit changes every time according to the total replenishment time, and this is plotted. As can be seen from FIG. 3, the ratio of recycled toner to unused toner in the developing container is Δr /
(R + m)｝ × 100 (%). If these calculations are constantly performed, the existence ratio of the recycled toner and the unused toner in the developing container can be known in real time.

Next, a second embodiment adopting the second invention will be described. Here, an example will be described in which the present ratio of the recycled toner and the unused toner in the developing container is calculated based on the history of the past 180 seconds. Again, the equation used in the first embodiment, a = − (r + m) / (χ ₀ + ψ ₀ ), χ
= {(Aχ ₀ + r) e ^at −r} / a. First, it is detected that the amount of the recycled toner in the collection container is small, and the existing ratio of the recycled toner in the developing container is a known value.
0.1 g (g / sec) of only unused toner is supplied to g developer. After a lapse of 600 seconds, the amount of the recycled toner in the collection container is detected to be sufficient, and the recycled toner is 0.05 (g / sec) and the unused toner is 0.1 (g).
/ Sec) Each calculation result when the control is switched to the adding control is shown below.

First, in the calculation 1, the history of the past 180 seconds after 180 seconds from the start indicates that only the supply of the unused toner
Since it has been 80 seconds, χ ₀ = 5, ψ ₀ = 45, r = 0,
From m = 0.1, a = −0.002, t = 180, χ =
3.488, which is (3.488 / 50) × 100 °
The result is 7.0%.

Similarly, in operation 2, χ ₀ = 3.488, ψ ₀
= 45.512, r = 0, m = 0.1, a = -0.00
2, from t = 180, χ = 2.434 and therefore 4.9
%. In the operation 3, χ ₀ = 2.434, ψ ₀ = 47.56
6, r = 0, m = 0.1, a = -0.002, t = 18
From 0, χ = 1.698, and therefore 3.4%.

In operation 4, the first 60 of 180 seconds
For the second, only the unused toner is supplied. Here, it is detected that the recycled toner in the collection container is sufficient, and the control of the toner supply is switched, and thereafter, the recycled toner and the unused toner are supplied for 120 seconds. In this case, χ ₀ = 1.698, ψ ₀ = 48.302, r = 0, m =
0.1, a = -0.002, t = 60 and χ =
3.0% is determined from 1.506, and then χ ₀ = 1.50
6, ψ ₀ = 48.302, r = 0.05, m = 0.1,
χ = 6.089 from a = −0.003 and t = 120, and the ratio of recycled toner in the developing container is 12.
2% is required.

Thereafter, in the calculation 5 and the calculation 6, the mixing ratio of the replenishment toner does not change in the middle, so that
1.0% and 26.2% are required. As described above, the present ratio of the recycled toner and the unused toner in the developing container can be known from the existing ratio of the recycled toner and the past ON / OFF history of the toner supply motor based on the result of the previous calculation.

In order to make the above description easier to understand, Table 5 summarizes the history of the switching control of the toner supply contents after 0 to 1,200 seconds and the ratio of recycled toner to unused toner. saw. FIG. 4 shows a plot of these.

[0030]

[Table 5]

Since the above calculation results and calculation results are not detected and the existence ratio of the recycled toner and the unused toner is obtained, the calculation is carried out gradually when supply toner of various mixing ratios is supplied or after a long time. There may be errors in the results. Further, if the contents of the memory are erased for some reason, the history of the past existence ratio held or stored may also be lost. Therefore, in the third embodiment employing the third invention, an operation is performed such that a predetermined percentage of recycled toner is intentionally provided. This is because, for example, if the current ratio of the recycled toner is unknown or if it is determined that it contains a large amount of error, the replenishment of the recycled toner in the developing container is continued if the replenishment is continued for a predetermined time at the mixing ratio of the predetermined recycled toner and the unused toner. And the presence ratio of unused toner converges to the value of the mixture ratio. FIG. 3 is used again to explain this.

The conditions were the same as in the first and second embodiments, and χ ₀ + ψ ₀ =
At 50 g, the recycle toner replenishing motor is used at a speed of 0.05 (g / sec) when rotating, and the unused toner is used at a speed of 0.1 (g / sec) when rotating. First, if the mixing ratio of the recycled toner is about 33% (the amount supply motor rotates) to the developer in which the existence ratio of the recycled toner in the developing container is unknown, the supply is continued for a sufficiently long time. , About 33%. This is because if the unknown existence ratio is 20%, the curve converges to 33% with the same curve as the condition A in FIG. 3, and even if the unknown existence ratio is 0%, the curve in FIG. It converges to 33% with the same curve as the condition B.

When the toner whose mixing ratio of the recycled toner is 0% is replenished, the abundance also approaches 0%. This is because the unknown abundance is 30% and only the unused toner is used. , It converges to 0% on the same curve as the condition C in FIG. However, in this case, considering that the normal abundance is in the range of about 10% to 35%, it takes a long time to converge, so it is not recommended.

The reset control of the existence ratio can be applied to the prior art. In some cases, printing with a developer that does not contain recycled toner is desired to temporarily require a higher-quality image, and in other cases, printing may be performed regardless of image quality. For example, when a specially beautiful image is required for a recycle copier of the type in which the ratio of recycled toner to unused toner in the developing container is not controlled and the collected toner is returned to the developing container as it is. For example, if the control to temporarily return the recycled toner is stopped and only the unused toner is replenished, the ratio of the recycled toner in the developing container will be low until the toner overflows from the cleaning or the transport path of the recycled toner. It becomes a good image because it becomes more and more. In this case, the control of the condition C is also effective. However, since there is no recovery container or a means for detecting recycled toner, which is a part of the constituent elements of the present invention, problems such as overflow of toner in the cleaning unit may occur.

As another example, Japanese Patent Application Laid-Open No. Hei 8-286513 (controlling the amount of unused toner in accordance with the amount of recycled toner transported to keep the mixing ratio below a predetermined value)
According to the technology, a problem is that when a large amount of recycled toner is generated, mixed toner is generated more than necessary. Here, when the user does not need to worry about the temporary image quality, a mode in which the amount of unused toner is controlled in accordance with the transported amount of the recycled toner to suppress the mixing ratio below a predetermined value is set. After stopping, the recycled toner is consumed as much as possible, and thereafter, the predetermined existence ratio can be set in the reset mode of the present invention. However, here too,
The technology described in Japanese Patent Application Laid-Open No. 286513 does not include a recovery container and a means for detecting recycled toner, which are part of the constituent elements of the present invention, and thus may cause problems such as overflow of toner in the cleaning unit. When the above-mentioned recycled toner is consumed as much as possible, it is recommended to use the T / D control described below.

Next, a method of controlling the T / D of the developer in the developing device will be described. In order to measure the T / D of the developer in the developing device 4, the developing device is provided with a toner control sensor 46 (magnetic permeability sensor). This output value is increased or decreased according to the amount of the magnetic material in the developer. When the T / D is low, the ratio of the magnetic material is high, and the output value is high, and when the T / D is high, the output value of the magnetic material is high. The output value is low because the ratio is low. T
In the control for maintaining / D at a desired value, first, a predetermined T / D
Is stored in a memory, and the output value of the tonac sensor at a desired T / D calculated based on this value and a data table prepared in advance is set as a threshold value. The output of the sensor is compared with this threshold value, and when the output value of the toner sensor is higher, a toner supply signal is output. In response, the toner supply motor is rotated to supply toner. This toner supply operation is continued until the output value of the toner sensor falls below the threshold value. Similarly, when it is desired to increase T / D, the threshold value is set low, and when it is desired to decrease T / D, the threshold value is set high.

However, other factors also affect the output of the toner sensor. For example, when the humidity rises, the charge of the toner in the developer decreases, so that the repulsive force between the developer particles decreases, and as a result, the density of the developer decreases. , And the output of the toner control sensor shows a higher value than the developer of the same T / D at normal humidity. Further, when the developer becomes old, the charge amount of the toner in the developer decreases due to a decrease in the ability of the carrier to charge the toner, and similarly, the output of the toner sensor is higher than that of the developer having the same T / D at normal humidity. Is shown. For this reason, in an actual machine, in order to reflect the above-mentioned influence on the control for maintaining the T / D, the control is performed based on the data of the counter of the temperature, the humidity and the developer and the control data prepared in advance. Here, since this correction has little relation to the present invention, the other data is omitted only as data of normal temperature and normal humidity.

Further, in the fourth and fifth embodiments employing the fourth invention, the existence ratio of the recycled toner and the unused toner in the developing container can be roughly detected and controlled, so that the ratio is determined according to the existence ratio. Toner control is being performed.

More specifically, the relationship between the ratio of the recycled toner and the unused toner in the developing container, the T / D, and the output value of the toner sensor is measured in advance, and control data is created based on the measured relationship. . In the present embodiment, as shown in FIG.
Is prepared, and control data is created based on data obtained by plotting the developer. In the figure, ○ indicates plots of the output values of the toner sensor of several types of T / D developer containing only unused toner, and similarly, Δ indicates the development of several types of T / D of toner containing 15% recycled toner. □ are several types of T / D developers containing 30% recycled toner. This data and the T / D range of the actual use area (here, T / D = 2.6 to
(5.4%) to create control data. Usually, a curve is plotted, but in an actual use area, it may be approximated to a straight line. This control data may be table data or may be held as a function. The data for controlling the toner density of the three patterns A, B, and C in the figure are as follows. When the pattern A is less than 5% of the recycled toner in the developing container, the pattern B is When the abundance ratio is 5 to 25%, the C pattern is obtained when the abundance ratio of the recycled toner in the developing container is 25% or more.

The case where the fourth invention is applied to the first invention will be described again with reference to FIG. Here, since the existence ratio of the recycled toner and the unused toner can be calculated in real time, the result is compared with the threshold value of each pattern determined above, and the control is switched to the toner density control of the appropriate pattern.

The case where the fourth invention is applied to the second invention will be described again with reference to FIG. Here, since the existence ratio of the recycled toner and the unused toner is calculated every 180 seconds, the toner density control of an appropriate pattern is performed based on the result of comparison with the threshold value of each pattern determined above. Can be switched.

FIG. 6 is a block diagram of an image forming apparatus employing the present invention. As can be seen, in the T / D control in the developing device, the recycle toner replenishment motor 65 and the unused toner replenishment motor 47 are controlled according to the recycled toner amount detection sensor 69 in the collection container.
Further, based on the counter 84, the temperature sensor 85, and the humidity sensor 86, the data for controlling the tongue control is changed.

[0043]

As described above, according to the first or second aspect of the present invention, the ratio of recycled toner to unused toner in the developing container can be known. Further, according to the third aspect of the present invention, even when it is determined that the existence ratio is unknown or has a large error, the existence ratio can be set to the predetermined existence ratio. Further, according to the fourth aspect of the present invention, since the toner density control data is switched in accordance with the ratio of recycled toner to unused toner in the developing container, accurate T / T
D control can be realized.

[Brief description of the drawings]

FIG. 1 is a schematic view of an image forming apparatus according to the related art.

FIG. 2 is a schematic view of an embodiment of an image forming apparatus according to the present invention.

FIG. 3 is a diagram illustrating a relationship between a time-existence ratio and the like, for explaining a first embodiment, a third embodiment, and a fourth embodiment of the present invention.

FIG. 4 is a diagram for explaining a second embodiment and a fifth embodiment of the present invention, and is a relational diagram such as a time-existence ratio.

FIG. 5 is a diagram showing the relationship between T / D and toner sensor output when toner concentration control data is obtained according to the present invention.

FIG. 6 is a block diagram of the present invention.

[Explanation of symbols]

 4, developing device 41; developing container 46; toner control sensor 47; unused toner supply motor 6; cleaning device 65; recycled toner supply motor 67; recycled toner transport path 68; collection container 69; means

Claims (4)

[Claims] An image forming apparatus for performing recycle development for re-supplying toner collected by a cleaning device to a developing container, an unused toner replenishing means for replenishing unused toner to the developing container, and a toner collected by the cleaning device Container, a recycled toner detecting unit for detecting the amount of recycled toner in the collection container, a recycled toner supply unit for supplying recycled toner from the collection container to the developing container, and a ratio of carrier and toner in the developing container. A toner density detecting means for detecting, a toner density controlling means for controlling a toner density based on an output value of the toner density detecting means, and a calculation result of an existing ratio of the recycled toner and the unused toner of the developer in the developing container. Holding means for temporarily holding the developer and the developer in the previous developer container held by the holding means. Based on the calculation result of the existence ratio of the recycled toner and the unused toner, the ON control of the unused toner replenishing unit, and the mixing ratio, the replenished toner amount, and the replenishment time obtained from the ON control of the recycled toner replenishing unit, in real time. An image forming apparatus comprising: a real-time presence ratio calculating unit that calculates and outputs a presence ratio between a recycled toner and an unused toner in a developing container. 2. An image forming apparatus for performing recycle development in which toner collected by a cleaning device is re-supplied to a developing container, an unused toner replenishing means for replenishing unused toner to the developing container, and a toner collected by the cleaning device. Container, a recycled toner detecting unit for detecting the amount of recycled toner in the collection container, a recycled toner supply unit for supplying recycled toner from the collection container to the developing container, and a ratio of carrier and toner in the developing container. A toner density detecting means for detecting, a toner density controlling means for controlling a toner density based on an output value of the toner density detecting means, a calculation result of an existing ratio of recycled toner and unused toner of the developer in the developing container, and History of ON time of unused toner replenishing means and ON of recycle toner replenishing means A storage unit for storing a history of time, and a calculation result of the existing ratio of the recycled toner and the unused toner of the developer in the previous developer container stored in the storage unit, and a history of the respective replenishment times, An image forming apparatus comprising: an existing ratio calculating unit that calculates an existing ratio between an unused toner and a recycled toner in a current developing container. 3. An image forming apparatus for performing recycle development in which toner collected by a cleaning device is re-supplied to a developing container. Unused toner replenishing means for replenishing unused toner to the developing container, and toner collected by the cleaning device. And a recycled toner detecting means for detecting the amount of recycled toner in the collection container, a recycled toner supply means for replenishing the development container with the recycled toner in the collection container, and a recycled toner for supplying toner to the development container. A mixing ratio control unit that controls a mixing ratio of unused toner, and the mixing ratio control unit, when the existence ratio of unused toner and recycled toner in the developing container is unknown or when it is determined that there is a large error, By keeping the mixing ratio of recycled toner and unused toner constant for a predetermined time, the developer container An image forming apparatus comprising: an existing ratio reset unit that performs control to make the existing ratio of the unused toner and the recycled toner therein substantially equal to the mixing ratio. 4. The image forming apparatus according to claim 1, wherein the control content of the toner density control unit is switched according to the ratio of unused toner and recycled toner in the developing container. .